This Phase II, multicenter trial has several primary objectives. The first is to evaluate the complete response rate, progression-free survival, and survival of patients with HIV-related intermediate and high-grade Non-Hodgkin's Lymphoma (NHL) treated with infusional cyclophosphamide, doxorubicin, and etopside (CDE) plus didanosine (ddI). Toxicity and event-free survival, such as death, progression of lymphoma, or AIDS-defining event, will also be evaluated. Patients will be statified according to CD4 counts and CNS involvement.